Trolley-ladder.



S. PUTNAM.

TROLLEY LADDER.

APPLICATION mm JAN. s, 1916.

1 1 88,99 1 Patented June '27, 1916.

Z SHEETS-SHEET I.

WITNESSES 2i INVENTOI? Jamaal Putnam BY W M ATTORNEVS S. PUTNAM.

TROLLEY LADDER. APPLICATION FILED JAN. 3.1916- 1,188,991 Patented June27, 1916.

2 SHEETS-SHEET 2.

WITNESSES INVENTOR Jamaal Patna/22 M K M y W ATTORNEY? Tm: COLUMBIAPLANOGRAPH co. WASHINGTON. n. c.

variation in the track 8.

@NTTED STATES PATENT @FFTQE.

SAMUEL PUTNAM, OF NEW YORK, N. Y.

TROLLEY-LADDER.

Specification of Letters llatent.

Patented June 27, 1916.

Application filed January 8, 1916. Serial No. 70,954.

To all whom it may concern Be it known that I, SAMUEL PUTNeM, a citizenof the United States, and a resident of the city of New York, borough ofBrooklyn, in the county of Kings and State of New York, have invented anew and Improved Trolley-Ladder, of which the following is a full,clear, and exact description.

Among the principal objects which the present invention has in view are:to provide means for normally holding a ladder of the type mentioned instationary position; to provide means for releasing the lad der topermit movement of the same to change the service location; and toprovide a simplified and inexpensive mechanism for controlling themovement of the ladder.

Drwwings.-Figure 1 is a side view of a top fragment of a ladderconstructed and arranged in accordance with the present in vention, thesame being shown in conjunction with a fragment of overhead rail forsupporting said ladder in service position; and'Fig. 2 is a back view ofa ladder having a track mechanism such as described.

Description-.As seen in the drawings, a truck 7 of conventional form issuspended from a hollow tubular track 8, the lower edges. 9 of which arecontracted to form a slot-like opening for the pendant legs 10. The legs10 are pivotally connected to frames 11, using for this purpose, pins12. The frames are permitted to rock on the legs 10 to allow the wheels13 to accommodate any The wheels are suitably mounted on pins 14.

The ladder proper has side stringers 15 which are suitably connected bystepslG of approved construction. Secured by a bolt 17 is a bracket 18.The bracket 18 is bifurcated to form bearings for a bell crank lever 19and for the pivot pin 20 thereof. The lever 19 has a handle 21 whichnormally rests at the rear of the ladder and sufliciently remote fromthe neXt lower step thereof, to avoid engagement by the foot of a personusing the ladder.

The truck 7 is preferably rigidly connected to or integrally formed witha tubular cross arm 22. In this way, the arm 22 is made rigid with thetruck 7 and is thereby disposed to form a steady bearing for a pivot rod23. The pivot rod 23 forms av pivotal bearing for the ladder and thestringers 15 thereof. To steady the bearing thus formed, the ends of thecross-arm 22 are flared to form bearing plates 24. The plates 24 on theinner sides of each of the stringers l5 and the washers 25 at the outersides of the said stringers, form substantial clamps for the saidstringers when the nuts 26 are set up on the screw-threaded end sections27.

The truck 7 is normally held in fixed service relation by a wedge shoe28. The shoe 28, as best seen in Fig. 2 of the drawings, has a fin 29,which constantly remains between the edges 9 to serve as a guide for thetruck. The shoe 28 is supported on a plunger 30, which is reciprocatedin a bearing formed in the enlarged end 31 of the truck 7.

The means employed for reciprocating the plunger comprises a spiralspring 32 which rests between the shoe 28 and the end 31, and a bellcrank lever 33, which is pivotally mounted by a pin 34: on the truck 7and directlyupon a pendant bracket 35 thereon. The lower or free arm ofthe lever 33 is operatively connected with the free end of the lever 19by a chain 36.

Operati0n-1Vhen thus equipped, a ladder of the character denoted isnormally held in stationary service by the spring 32 forcing the shoe 28and fin 29 also between the edges 9 of the track 8. Thus the ladder isprevented from moving while a person is entering thereon and in factuntil he has reached a point in climbing the ladder to engage the handle21. Having climbed to the position Where he may manipulate the handle21, the user of the ladder being prepared to move the same, grasps thehandle 21 and rocks the lever 19 to draw downward on the lever 33. Thelever 33 being thus rocked, depresses the plunger 30 and compresses thespring 32 until the shoe 28 and fin 29 release their engagement of thetrack 8. While the operator now holds the handle 21 in the positiondescribed, the ladder may be freely moved on the track 8. WVhen havingarrived at a new desired service position, the operator releases thehandle 21, the spring 32 lifts the shoe 28 into holding engagement withthe edges 9 of the track 8. The truck 7 is now prevented from beingmoved and a new service position of the lad der becomes fixed until theoperator again manipulates the handle 21 of the lever 19.

Claim:

A trolley ladder comprising a tubular overhead track; a wheel-supportedtruck mounted Within said tubular track to move lengthwise thereof; abrake mounted on said truck, said brake having a wedge-shaped member forpartially entering to engage said track; a spiral spring supporting saidWedgeshaped member; a plunger; a bell crank lever operatively connectedwith said brake to separate the head thereof from engagement with theoverhead track; and means for operating said lever, said means embodyinga handle disposed adjacent the upper end of said ladder.

In testimony whereof I have signed my name to this specification 'in thepresence of two subscribing witnesses.

SAMUEL PUTNAM.

Witnesses E. F. MU'RDOCK, G. H. EMSLIE.

Copies of this patent may be obtained for flvc cent: each, by addressingthe Commissioner 0! Patent: Washington, D. 0."

